Patent GB-1404131-A (GB)
Title: Food treatment machine
IPC: A23N7/00
Filed: 1971-04-14
Abstract: 1404131 A machine for treating onions R JONES (ENGS) LONDON Ltd 5 July 1972 [14 April 1971] 9368/71 Heading A4C In an onion skinning machine, onions on the upper run of an endless chain conveyer are held by plungers 61, Fig. 5, of a retaining mechanism also comprising an endless chain parallel to said upper run, the zone between the conveyer and the retaining mechanism being provided with a topping and tailing mechanism, a skin removing device and feed means therefor being mounted at the discharge end of the conveyer. The skin removing device, Fig. 7, comprising a plurality of cups 121 arranged around the periphery of a rotatable turret 120, each cup having a helical device, e.g. a groove 124, and a nozzle (125), Fig. 6 (not shown), such that an onion dropped into a cup is rotated by a fluid jet issuing from the nozzle to engage the helical device and move down into the cup, thus removing the outer skin. Each onion is held by an onion retaining  mechanism 22 on a conveyer 20 and travels past topping and tailing mechanisms e.g. 23 and skin slitting mechanisms 25 and 26 before dropping into a cup of the skin removing device. The rotatable turret 120, Fig. 7, is mounted on a stationary shaft 122. Air is supplied through an axial port 126, cross-bores 127 and a peripheral groove (131), Fig. 6 (not shown) in the shaft to pass to the nozzles (125) via the bores 129 in the turret. Each cup has a helical groove 124 and the nozzle (125) is positioned to direct an approximately tangential jet into the cup. The peripheral groove (131) extends around only part of the shaft circumference such that air is not supplied to the cups while in their lowest position. The CONVEYER 20, Fig. 1, comprises an endless chain 30 arranged around sprockets 31 and 32, the onions being impaled on the needles (43) Fig. 1B (not shown), of supporting "V" blocks 37 mounted on the chain. The onions travel with their root-stem axes perpendicular to their direction of motion. An ONION RETAINING MECHANISM 22, Fig. 1, positioned above the conveyer comprises an endless chain (50), Fig. 2 (not shown), arranged around shafts 52 and 53 and has pins 61, Fig. 5, mounted for sliding movement relative to the chain. Guide rails (69), Fig. 2A (not shown), allow the pins to drop under their own weight on to an onion and retract the pins for their return movement. TOPPING and TAILING MECHANISMS, Fig. 4C, each comprise a rotary knife 70 driven by a compressed-air motor 71. Each motor and knife assembly is mounted for horizontal movement on bars 73 and 74 enabling the distance between the topping knife and the tailing knife to be automatically adjusted by the engagement of guide rods 90 and 91 with an approaching onion. The guide rods are mounted on the motor and knife assembly but are free to move in a vertical direction. The SKIN SLITTING MECHANISMS 25 and 26, Fig. 5, each comprise a knife mounted on an arm 110 pivotally mounted about a vertical axis. The arm 110 is biased towards an approaching onion by a weight connected by a cord 113. The knife of mechanism 25 swings as the onion passes to slit the onion skin from the leading edge around to one side of the onion. The knife of mechanism 26 acts in a similar way to slit the other side of the onion. A nozzle 115 is provided on each of the arms 110 to direct a jet of air on to the onion and lift the skin.